Chain coding streamed images through crack run-length encoding

Conventional chain coding techniques require random access to the input image. For stream processing, it is necessary to perform all of the processing in a single raster based scan. An FPGA implementation adds the constraint of processing one pixel per clock cycle. A new algorithm that meets these constraints is described. It is based on run-length encoding the horizontal cracks between object and background pixels. If necessary, the crack run-length code can be converted to a Freeman chain code for subsequent processing.